Signal sending device within automatic telephone system



May 13, 1952 K. G. JOHNSON ET AL 2,596,245

SIGNAL SENDING DEVICE WITHIN AUTOMATIC TELEPHONE SYSTEM Filed Dec. 2a, 1948 11 L R; H

RIIRZ R3 R4 T'll Fig.3

JNVJENTORS KBRL EORG J OH'N N NILS VfiLDfiMfiR HOFSTREND PH TORNEYS Patented May 13, 1952 SIGNAL SENDING DEVICE WITHIN AUTO- MATIC TELEPHONE SYSTEM Karl Georg Johnson and Nils Valdemar Hofstrand, Stockholm, Sweden, assignors to Telefonaktiebolaget L M Ericsson, Stockholm, Sweden, a company of Sweden Application December 28, 1948, Serial No. 67,584 In Sweden January 9, 1948 2 Claims. (01. 179-18) In telephone networks with local traffic as well as toll trailic, communications of difierent kinds, e. g. local and toll communications, are carried over the same lines. Inasmuch as different conditions are needed for different kinds of communications, signals indicating the kind of communication must be sent over the lines. Fhe present invention refers to a method for transmission of such signals from a calling to a called telephone exchange.

This is achieved, at automatic telephone exchanges with registers, in which diiierent kinds of communications are forwarded under control of the same sending register at the called exchange by certain impulse series e. g. the first or the last in a subscribers number sent at the setting for a communication of one kind and not containing more than at the most a certain number of impulses determined beforehand for all such communications. For another kind of communication there is provided at least one of said impulse series which comprises a determined fur ther number of impulses or a multiple of said further number, which number is at least as great as the first mentioned number.

By means of this invention a number of differ ent signals can be produced. For each impulse series corresponding to a figure and transmitted from the initiating exchange for a communication to its end exchange, it is possible to add e. g.,

impulses, which means different signals, e. g. that the communication is a toll call if the signal comes at the first received impulse series, or that all the figures have been sent if the signal comes at the last received impulse series. Both signals can be applied to the last series of impulses by having an addition of 10 impulses marking that all the figures have been sent and an addition of 20 impulses marking additionally, that the communication is a toll call. It is evident that a great number of different signals can thus be pro duced.

The invention will be described below in its simplest embodiment with reference to the accompanying drawings Figs. 13.

Fig. 1 shows a general diagram of a connection between a toll exchange and a local exchange.

Fig. 2 shows the necessary devices in a toll reg ister for sending of signals according to the invention.

Fig. 3 shows the necessary receiving devices for the signals in a local register, setting local as well as the local part of toll communication.

In Fig. l, L is a junction line or a series of junction lines interconnected by means of selectors connecting a telephone exchange I with a telephone exchange IL Local as well as toll communications are supposed to be set over line L under control of an operator. At the setting of a communication, the line L is connected to a sending register RES by means of a push button TL. The number of the called subscriber A is dialled on the keyset K and registered in the register RES. After all the figures having been dialled the push button TS is pressed down, whereafter impulse series corresponding to at least a part of the dialled figures are emitted over the line L to the receiving register REM in the called exchange II. Register REM then sets the selectors GV and LV, whereby the connection between the exchange I and the subscriber A has been completed. If the communication is to be considered as a toll call and have the preference before local calls in the exchange II, the operator presses the push button TJ before the push button TS is actuated whereby such a connection of the register RES is obtained, that the lastimpulse series is increased with 11 impulses. Fig.2 shows how this is rendered possible. We suppose that RES is a register for three digits. The three digits are registered in the selectors Vl-V3, all of which have 11 positions and at rest are in their 11th position. When the push button TS is pressed down the following circuits are closed: (a) push button TS, winding on relay R3, the 11th position of selector Vlil, winding on relay R2 to negative. The winding of relay R3 has a high resistance, whereby relay R2 does not attract its armature. Relay R3, on the other hand, actuates the contacts 3|33. The magnet SM of the selector S receives current over contact 33 and attracts its armature. The selector S is driven step-by-step, and its brush-set moves when the driving magnet SM releases its armature after a current impulse (b) push button TS, contacts 42, I3 and 24, winding on relay Rl to negative. Relay RI is provided with two windings counteracting each other, of which one is connected in series with a condenser. It is thereby obtained, that the relay attracts its armature with some delay and also releases its armature with some delay after make. Relay RI attracts its armature and the contacts l2--Hl are actuated. The driving magnet VM receives current over contact M and attracts its armature. The magnet VM pertains to the selector VIO, which is of the same construction as selector S. Relay RI has a selfinterrupter l3 and will therefore break and make repeatedly and send current impulses over the contacts 12 and i4. After the first impulse sent ture.

by relay R! the brushes of selector Vlfl move one step. .ihe circuit over its 11th position through relay R3 is broken. Relay R3 releases its arma- Contact 33 breaks the current for magnet SM, the brushes on selector S are moved to position 1. 'If .the selector V! is set in position 1, the following circuit is closed: selector S position 1, selector Vi position 1, selector VH3 position 1, winding on relay R2 to negative. Relay R2 attracts its armature. Contacts 2i-'-2 l are actuated. Relay R2 is self-held over contact 22 and contact 4!. The impulse sending fromrelay R5 is broken by contact 24. .Selectorvlil is driven to position 11 by magnet VM, whichreceives current over the self-interrupter 2i! and contacts 32 and 23. When the brushes of selector V it. reach position 11, relay R3 attracts its armature. Contact S2 breaks the current for driving magnet VM. Relay R4, which is slow-releasing, receives current over contacts 2.! and 31 and attracts its armature. Contacts 4i-42 .are actuated. The holding "circuit for relay R2 is'broken by contact 3 H. Since relay Rsihas .a high resistance, .relay R2 releases its armature. Contact 33 closes the :ClI'Cllill'fOl magnetSM and prepares the move of If the'selector VI is not in position .1 but in some other position, e. g."5, the connecting processidescribed abovewill be postponed until selector V10 has stepped topositionfi .by means of impulses from contact Mon relay .Rl. impulses to'the line .L and the register REM .in Fig. l.

Forleachimpulse series, which. is sent, the selector :S is moved one. step. When the third and :last impulse series :is beginning, selector S is in position.2 and relay R3 and .magnet SM keep theirarmatures attracted. After the end of the Zfil'Sl? impulsethezselector S steps to position 3, but

immediately move to position-4 if the push button IlJ .is not pressed .down, due to the magnet SM receiving current over position *3 in selector S, contact 51 and the self-holding contact 5! When selector S stands in position 4, relay R2 re- :ceives current astsoon as selector VI has stepped .to the position corresponding to the setting of selector V3.

.Ifhowever the communication is a toll call, the ioperator has pressed the button TJ and relayltfi has attracted its armature so, that contact i is actuated. When the selector S reaches position 3, his not moved to position-4 until VH1 has passed its 11th position, whereby relay R3-attracts its armature and contact 3-3 is closed .for a moment. Selector S thereby moves to position 4 simultaneously with selector VH1 leaving its 11th position. Hereafter as many impulses are sent, as correspond to the setting of the selector V3. The lastimpulse series will thereby comprise 11 impulses morethanis required for the indication of the last figure. V

In .relay systems, the selector Vl'il is replaced by a relay chain, which can be momentarily moved back to its initial position after impulses, whereby an addition of 10 impulses more than is required for the indication of the last relation to the last figure, e. g. indicating that all the figures have; been sent, which is necessary if .35 simultaneously come over contact I2 and wire ti the number of figures varies at difierent communications and there is no other signal indicating to the register REM when it can disconnect itself from the connection. It is thus obtained, that at leastvll' additional impulses areralwayyadded at sending ofthe last figure zand, ifi'furthermore the push button TJ is pressed down, the selector Vlil must pass the position 11 twice, once to move the selector S from position 3 to position 4, and once to move it'from position 4 to position 5. 22 additional impulses will thereby be sent in relation with the lastv figure. V

:Fig. shows the impulse receiving device for "thelthird'figure'in the register REM. in Fig. 1. From an impulse receiving relay, which is not shown in the figure, the impulses coming in over line'fLare transmitted to wire t2 and the driving magnetDMi; for a step-by-step driven selector I93 with 11 positions, of which position 11 is the initial position. At the beginning of the first impulse,

the slow releasing relayR'll attract'sits:armaposition 11, contacts-liar! and windir'rg on .relay Bi 3 to negative.

Relay :Rit attracts -its armature, contact 134 .is closed, but the :relay cannot attract wholly beforeselector D3 hasleft position 11 whereby thefollow-ing circuit iSfClOSQdI from .a-contact. on a holding relay which isnot shown in the figure,-contact 1-34, both thewindings on relay R43 in series, to negative. :Relay Rl3 actuates thecchtacts Isl- 133. vvIf-rllamo're impulsesare coming -in,-.relay RM" will attracti'ts armature when selector D3 passes position 11 for the second time. Contacts: l*4l--'i'43 iar'e thereby actuated and relayz-Rllis self held.

After the end of the impuise series,:r'ela'y RH releases its armature: and :a'circuit is :closed over the contacts I I l,. l tliand Ml-"or l lzdepending on if 11 or 22 additional impulses have beenreceived. This circuit represents the signal transmitted together with thethird 'figure.

The connection shown'in'l ig. 3 can naturally be arranged for any figure in the register-REM, whereby the purpose of thesignals-jean be chosen according to need.

We claim:

1. In telephone systems 0 the type including a first exchange, a second exchange, .a junction line joining said exchanges; in'said first exchange a sender containing a, register mechanism, means for setting said register mechanism in accordance with a called-subscribers telephone designation, means for connectingsaid'sender 'tosaid junction line, means "in said sender'fo'r sending impulse series representing thesub'scribers -telephone designation registered in said register mechanism over said junction line; in saidsec- 0nd exchange subscribers lines, 'selectorsxand a register for setting communications tos'ai'di'subscribers lines over said *selectorspmeans for conmeeting said second register to saidjuncti'on line by a call from said first exchange andregistering means in said second register set by the impulse series sent by said sender; the combination there- Cohtact H! :is actuated. Selector 1331s 5 with or means for sending signals indicating the kind of communication comprising in said sender control means having a number of contact positions and arranged to successively engage all said positionsfor each impulse series and a relay connected to be energized from each impulse series by said control means engaging one of said positions marked by said first exchange register mechanism; signalling means for causing additional impulses in at least one of said impulse 10 tions the number of times determined by said signalling means; and means in said second register for recording the number of additional impulses.

2. In an automatic telephone system as described in claim 1, means for causing 11 additional impulses in at least one of said impulse 6 series and 22 additional impulses in the same said impulse series in a subscriber's telephone designation.

KARL GEORG JOHNSON. NILS VALDEMAR HOFS 'I'RAND.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,729,856 Tench Oct. 1, 1929 1,882,106 Wise Oct. 11, 1932 1,901,156 Gillings Mar. 14, 1933 1,903,019 Wright Mar. 28, 1933 2,107,988 Kardorfif Feb. 8, 1938 2,374,884 Newby May 1, 1945 2,467,490 McClew Apr. 19, 1949 FOREIGN PATENTS Number Country Date 489,545 Great Britain July 25, 1938 

